Two young girls, Margaret and Lisa, are set to take the overnight train from Munich in Germany to stay with Lisa's parents in Italy for Christmas. On boarding they find the train is full and are forced to sit in the corridor. Meanwhile, two petty criminals, Blackie and Curly, also board the train as it is leaving Munich to escape from a pursuing policeman. The two thugs come across Margaret and Lisa who help them hide from the ticket collector. Blackie then encounters an upper-class blonde older woman who he makes to molest in the toilets only for her to aggressively seduce him. As Curly gets into a fight, the girls become increasingly wary of the two thugs' behaviour and make their way further down the train to escape them.